Summary Birth weight, which is subject to differences in prenatal nutrition, increased with parities to the fifth among the subhumid zone (SH = 1.89 kg) dams and to the sixth among the humid zone (H = 1.71 kg) dams. Seasonal influence did not significantly affect birth weights in either zone. Litter type had the greatest influence on birth weight, growth rate, and viability at 60 days of age, among lambs in both zones. The dual advantage of higher birth weight of lambs and higher postpartum weight of their dams, with the benefit of the maternal effect that supported optimal postnatal development lambs, resulted in higher body‐weight gain at 60 days of age at sixth parity (H = 6.17 kg; SH = 6.99 kg). In both zones, viability was optimum at the fifth parity (H=95.0%; SH = 95.6%). For all weight traits, single lambs (H = 7.73 kg; SH = 8.48 kg) were significantly (p < 0.05) and consistently superior to twin lambs (H = 6.68 kg; SH = 7.31 kg) at the natural weaning age of 105 days. At birth, female lambs were 6.4% behind male lambs in their subsequent growth up to natural weaning, even when the birth weight of both sexes was similar. In both zones, the viability showed an upward trend, with an increase in percentage of lambs weaned up to the fifth parity (H = 80.0%; SH = 90.1%) and a rapid decline after the sixth parity. The postpartum weight and higher parity, together with the postnatal maternal effect of dams' performance on growth in the first 60 days, influenced lambs' weaning weight at 105 days. There was no significant seasonal pattern of growth. At 210 days of age, the influence of litter type started to diminish. Differences in body weight due to sex also became relatively less important at this age. The ewes which had gained rapidly in weight appeared heavily pregnant, and with full udder, at 210 days of age. These findings confirm the importance of the transient nature of growth between 90 and 105 days of age. The physiologically mature weight is reached at higher parity, between the fifth and sixth, antibody weights of 20.93 and 23.59 kg for the humid and subhumid zone ewes, respectively. The mean liveweight considered to be a measure of physiological maturity was attained between 3.5 and 4.0 years of age. Résumé Etudes sur la production ovine traditionnelle dans la région humide et sub‐humide d'Asante (Ghana). III. Relations entre le poids de naissance et le développement du poids du corps avant et après le sevrage Le poids de naissance était fonction de l'influence d'alimentation prénatale variante. Il augmentait jusqu'au point du cinquième agnelage dans la zone sub‐humide (1,89 kg) et du sixième agnelage dans la zone humide (1,71 kg) montrant une dépendance directe du poids des brebis. Dans les deux zones climatiques, on n'a observé aucune influence saisonnière significative par rapport au poids de naissance. Le type de la portée (c.‐à‐d. portée individuelle ou multiple) avait l'influence la plus grande quant au poids, au développement du poids et au taux de survie des agneaux jusqu'au soixantième jour. ...

This studies presented in this paper were undertaken on 42 households units in two ecological zones of four farming villages located in the heart of the Kumawu Traditional Area (KTA) in Asante. The traditional area is the largest (9256 km(2) ) of the 21 traditional areas or paramouncies comprising the Asante Region (24 390 km(2) ), one of the ten regions of Ghana. The headquarters are in the township of Kumawu, which is located 56 km north-east of Kumase, the capital of the Asante Region. A brief discription of physical conditions, the land tenure system and the current agricultural resources of the area are given. Detailed descriptions of the physical characteristics of sheep type, ownership pattern and management practices, as well as flock structure, are discussed. The availability of fodder plants and their seasonal cover are outlined. In all, the studies covered 700 dams with almost 1500 lambings over a period of 30 months. ZUSAMMENFASSUNG: Untersuchungen über traditionelle Schafproduktion in der Humiden und Sub-humiden Asanter Region Ghanas. I. Natürliche Standortbedingungen und Resourcenausstattung im Untersuchungsgebiet Die Untersuschungen wurden in zwei unterschiedlichen agro-ökologischen Zonen in 42 kleinbäuerlichen Haushalten von 4 Dörfern durchegeführt. Es handelt sich um das Kumawu-Gebiet (9256 km(2) ) der Asanteregion (24 390 km(2) ) 60 km nördostlich von Kumase, der Hauptstadt der Asante mit traditionell sehr starker Schafhaltung. In der 1. Mitteilung wird eine detaillierte Beschreibung der natürlichen Standortfaktoren, Landeigentumsverhältnisse und landwirtschaftlichen Resourcenaussttatung gegeben. In einer Untersuchung über 30 Monate an 700 Mutterschafen mit ca. 1500 Geburten werden zunächst Schafrassen, Management und Eigentumsverhältnisse sowie Herdenstrukturen analysiert. RÉSUMÉ: Analyse de la production ovine traditionnelle (Djallonké) dans la région humide et sub-humide d'Asante du Ghana. I. Conditions naturelles du milieu et disponibilité de ressources dans la région d'enquête Les enquêtes ont été effectuées dans deux zones agro-écologiques différentes, soit dans 42 petites exploitations agricoles faisant partie de quatre villages. Il s'agit du territoire traditionnel de Kumawu, territoire le plus vaste (9256 km(2) ) dans la région d'Asante (24 390 km(2) ), à 56 km nord-est de Kumase, la capitale d'Asante, òu on se dédie traditionnellement à l'élevage intensif des ovins. L'article donne une brève description des facteurs naturels du milieu, de la structure agraire et des ressources agricoles de la région. L'enquête, effectuée pendant 30 mois, sur 700 brébis et à peu près 1500 parturitions s'est dédié d'abord à l'analyse des races bovines, aux pratiques de gestion, aux structures de propriété et celles des troupeaux bovins. Les enquêtes suivantes ont étudié les techniques de production, la reproduction, la commercialisation et les aspects économiques en tant que base d'une intensification de la production.

Summary In both zones, single lambs had significantly better productivity indices than twins; the lower indices were observed among primiparous ewes. The values of Index I showed the highest productivity at the fifth and sixth parities among the humid‐ and subhumid‐zone ewes. The effect of parity on Indices II and III was highest in the second and third parities among semi‐tethered and free‐range ewes, respectively. Better indices were recorded for ewes that lambed in the dry‐harmattan and transitional dry‐wet seasons, than for those lambing in either major‐wet or dryspell‐minor wet seasons in both management systems. The overall results largely confirm the increased superiority of the free‐range ewes over the semi‐tethered ewes: 6.3% heavier lambs up to natural weaning age; 9.8% shorter parturition intervals; 10.6% higher viability rate up to natural weaning, and 10.4% higher post‐partum weight of the dams. Résumé Dans les deux zones les brebis simples montraient un meilleur indice de productivité par rapport aux brebis jumaux. Les brebis issus de la première mise bas (primiparous) étaient désavantagés par rapport aux brebis provenant des mères plus àgées (multiparous). L'indice I accusait la plus haute valeur à la cinquième (zone humide) et sixième mise bas (zone sub‐humide), les indices II et III accusaient la plus haute valeur à la deuxième et troisième mise bas. Dans les deux zones climatiques de meilleurs indices de mise bas étaient observés dans la periode sèche de l'Harmattan et dans la phase de transition de saison sèche à la saison pluvieuse, contrairement aux mises bas à la grande saison des pluies ou à la petite ‘Dryspell’ saison pluvieuse. En tout il y résulte un avantage significatif pour les trois indices chez les meres en divagation libre: 6,3% de brebis plus lourds au moment de sevrage naturel; 9.8% d'intervall de mise bas plus court; 10,6% d'aptitude de survie plus forte au moment de sevrage; et 10,4% de poids Post‐partum plus élevé des mères. Zusammenfassung Untersuchungen über traditionelle Schafproduktion in der humiden und sub‐humiden Asanter Region Ghanas. V. Produktivitätsindizes In beiden Zonen wiesen Einzellämmer bessere Produktivitätsindizes auf als Zwillingslämmer. Erstlingslämmer waren gegenüber Lämmern von älteren Muttertieren benachteiligt. Index I erreichte die höchsten Werte zur fünften (humide Zone) und sechsten Ablammung (sub‐numide Zone), die Indizes II und III waren zur zweiten und dritten Ablammung am größten. In beiden Klimazonen wurden bessere Indizes erreicht für Ablammungen in der Trocken‐Harmattan‐Periode und der Übergangsphase Trocken‐ zu Regenzeit im Gegensatz zu Ablammungen in der Hauptregenzeit oder der kleinen ‘Dryspell’‐Regenzeit. Insgesamt ergeben sich signifikante Vorteile bei allen drei Indizes für die freilaufenden Muttertiere: 6,3% schwerere Lämmer zum natürlichen Absetzzeitpunkt; 9,8% kürzere Zwischenlammzeiten; 10,6% höhere Überlebensfähigkeit zum Absetzzeitpunkt; und 10,4% höheres Post‐partum‐Gewicht der Muttertiere.

IntroductionThe natural conditions, agricultural resources, period of study, and criteria used in the initial survey have been described by London and Weniger (1 994). The reproductive rate and prolificacy (LONDON et al. 1994), as well as the relevance of maternal influence on birth and preweaning weight, and the pattern of lambs' growth, from birth up to physiological maturity, have been discussed in previous contributions to the series (LONDON and WENI- GER 1995).No studies have investigated the mortality classifications listed below, in relation to birth weight in Djallonki sheep over a period of 2 years in traditionally managed systems in Ghana. However, valuable information on mortality rates has been given recently by ASARE and WILSON (1985), TUAH and BAAH (1985), TUAH et al. (1987), and KABUGA and AKOWUAH (1990) for the humid and subhumid zones of Asante, Ghana.Therefore, these investigations have aimed to determine the levels and causes of mortality of lambs in the following categories:1. Those known to have died within 14 days after birth and classified as neonatal, due 2. Those dying between the periods of post-neonatal (from 14 days of age) and pre-3. Those dying between preweaning age and natural weaning at 105 days of age. 4. Those dying as weaned (over 105 days), yearling, and adult sheep.In the field, low birth weight was a common cause of mortality, and this analysis determined the extent to which this contributed to the mortality rates. This has prompted observations of some of the intrinsic and extrinsic factors that interact with the management systems of the two climatic zones, and influence neonatal lamb survival or mortality. The results of this study should provide information on low-birth-weight-related mortalities, as well as changes in ewes' performance, and should form the basis for improvements in future husbandry and routine culling practices.mainly to low birth weight as well as to specific causes. weaning age (60 days of age). Materials and methodsThe extent and the main causes of losses, excluding premature and stillbirths, from the beginning to the end of the study, are discussed in this report. Losses due entirely to ' A link research programme between the